Nitrohydroxyethers



States Patent 3,402,208 NITROHYDROXYETHERS John A. Frump, Terre Haute, Ind., assignor to Commercial Solvent Corporation, New York, N.Y., a corporation of Maryland No Drawing. Continuation-impart of application Ser. No. 588,718, Oct. 24, 1966. This application Oct. 30, 1967, Ser. No. 679,189

- 1 Claim. (Cl. 260615) ABSTRACT OF THE DISCLOSURE Nitrohydroxyethers of the formula R1 R1 J(CHR4) ;R

wherein R is a member selected from the group consisting of methyl and hydrogen; wherein R is a member selected from the group consisting of alkyl radicals, for instance, of about 1 to or carbon atoms, including lower alkyl radicals; lower hydroxyalkyl radicals, for instance, of up to 5 carbon atoms; and a radical having the formula (CH R wherein R in the above formula and radical is selected from the group consisting of and | OH OH NO;

wherein R R R R x and y have the values assigned them above which are useful as corrosion inhibitors bactericides, pigment wetting and dispersing agents, emulsifiers and intermediates in the preparation of nonion ic surface active agents. Exemplary of such aminohydroxyethers is 2 methyl 4 oxa-6-hydroxy-6-vinyl-2- hexylamine.

Cross reference to, related applications This application is a continuation-in-part of copending application Ser. No. 588,718, filed Oct. 24, 1966 and now abandoned. Application Ser. No. 588,718 is a division of'application Ser. No. 302,470, filed Aug. 15, 1963, and now US. Patent No. 3,296,313. Application Ser. No. 6 302,470 is a continuation-in-part'of abandoned application Ser. No. 8,234, filed Feb. 12, 1960.

Summary of the invention 'My invention relates to a new group of nitrogen compounds and a process for their preparation. More particularly, it relates to a catalytic process for oxyalkylating 3,402,208 Patented Sept. 17, 1968 nitroalcohols and nitropolyols with epoxides and the novel nitro and amino-hydroxyethers obtained thereby.

The novel nitrohydroxyethers, compounds A, of the invention are those having the following general formula:

wherein R is a member selected from the group consisting of methyl and hydrogen; wherein R is a member selected from the group consisting of alkyl radicals, for

instance, of about 1 to 10 or 20 carbon atoms including lower alkyl radicals; lower hydroxyalkyl radicals, for instance, of up to 5 carbon atoms; and a radical having the general formula: (CH R wherein R in the above formula and radical is a member selected from the group consisting of the radicals wherein R is a member selected from the group consisting of hydrogen, phenyl, nitro-substituted phenyl, halosubstituted phenyl, alkyl, hydroxyl-sub'stituted alkyl, halosubstituted alkyl, alkene, and phenyl-substituted alkyl radicals; y is an integer ranging from about 1 to 10 or 20, and x in the above formula and radical is an integer ranging from about 1 to 20.

The novel nitro compounds of my invention can be prepared by contacting an epoxide with a nitroalcohol having the formula:

wherein R, has the above meaning and wherein R is a member selected from the group consisting of alkyl radicals of 1 to 20 carbon atoms, for instance, including lower alkyl radicals; and lower hydroxy alkyl radicals, for instance, having from about 1 to 5 carbon atoms; and x is an integer ranging from about 1 to 20, in the presence of catalytic amounts of boron trifiuoride or p-xylenesulfonic acid. Examples of suitable nitroalcohols are 2-nitro-2-methyl- 1 -propanol, 3-nitro-3-methyl-2-butanol,

tris (hydroxymethyl nitromethane, 2-nitro-2-propyll -prop anol, 2-nitro-2-methyl- 1 -octanol, 2-nitro-2-propyll-tridecanol,

2 -nitro-2-ethyl- 1 -nonadecanol, l2-nitro-12-methyll-tridecanol, l8-nitro-18-methyl-1-nonadecanol, 6-nitro-6-ethyl-1-heptanol,

tris (hydroxyethyl nitromethane, tris (hydroxybutyl nitromethane,

and the like.

Detailed description In the process for producing my new nitro compounds,

5 I generally employ temperatures ranging from about 0 C. to about C. At temperatures above 150 C. decomposition of the new compounds may occur. Temperatures below 0 C., even though allowing formation of my new compounds, would not be economically practical due to the requirement for expensive cooling equipment. While a broad temperature range of from about 25 C. to about 150 C., for instance, is suitable for my process, I prefer to use temperatures ranging from about 60 C. or 90 C. to about 130 C. When temperatures below the melting points of the nitroalcohols used in my invention are utilized, I prefer to use a solvent for the nitroalcohol which solvent is inert to the reactants and the reaction product. Examples of solvents which are useful include isopropyl ether, chloroform, dixoane, and the like.

Satisfactory results can be obtained in my process for producing the novel compounds of my invention by using small or catalytic amounts of boron-trifluoride or pxylenesulfonic acid catalylst in the reaction mixture. It was surprising to discover these catalysts since other acidic catalysts were found to be unsatisfactory. Catalytic amounts of boron trifluoride or p-xylenesulfonic acid ranging from about 0.05 to about 0.5% or 5% based on the weight of the nitro alcohol can generally be utilized but boron trifluoride is preferred. However, if desired, more or less than this amount can be used. In utilizing the boron trifluoride catalyst in my process, I prefer to form a complex with a compound inert to the reactants and the reaction products, for example, an ether. Representative ethers which I have found to be useful in forming complexes with boron trifluoride include sopropylether, dimethyl ether, diethyl ether, dibutyl ether, and the like. I prefer a complex of boron trifluoride-diethyl ether containing about 45 to about 50% by weight of boron trifluoride based on the weight of the complex. Although free boron trifluoride is a suitable catalyst in my process, its complexes with the ethers aforenamed are much easier to handle, use and store under ordinary industrial conditions, thus making them preferable to free boron trifluoride.

The molecular proportions used in producing the new compounds of my invention can vary considerably depending on the nitroalcohol and epoxide used and/ or on the final product desired. Ordinarily, mole ratios of nitroalcohol to epoxide of not less than 1:1 and not more than about 1:10 or 1:20 are useful in my process.

The epoxides from which I prepare my compounds must contain at least one grouping. Representative epoxides include alkylene oxides such as ethylene oxide, butene-l-oxide, isobutylene oxide, butadiene monoxide, 1,2-epoxyoctane, 1,2-epoxytetradecane, 3,4 epoxy 1 butanol, 1,2-epoxynonadecane, etc.; alkylene dioxides such as butadiene dioxide, etc.; halosubstituted alkylene oxides such as chloropropylene oxide, bromo propylene oxide, etc.; phenyl-substituted alkylene oxides such as 1,2-epoxyethylbenzene, 1,2-epoxyoctylbenzene, 1,2-epoxyheptadecylbenzene, etc.; nitro-substituted phenyl-substituted alkylene oxides such as 1,2- epoxyethylnitrobenzene, etc.; halo-substituted phenyl-substituted alkylene oxides such as 1,2-epoxy chlorobenzene, styrene oxide, and the like.

The novel nitro compounds of my invention can be reduced by any suitable reducing procedure to the corresponding amines. Thus, the method of the invention provides a novel and eflicient means for obtaining novel aminohydroxyethers, compounds B, having the general formula:

wherein R R x and R have the values assigned to them above. It should be noted that my attempts to obtain these aminohydroxyethers by oxyalkylation of the corresponding amino alcohols proved unsuccessful since the oxylating agents were found to preferentially add onto the amino group rather than the hydroxyl group. This preferential addition is expected since the amino group is more reactive than the hydroxyl group and it was thus surprising to find that the novel amine compounds of the present invention could be produced by oxyalkylating the novel nitro compounds to the corresponding novel amine com pounds of the present invention. Because the amino compounds of the present invention are more stable and can be titrated, the structures of the'nitro compounds are more easily determined in terms of the structures of the corresponding amino compounds.

In another aspect, the method of my invention affords the production of a novel group of aminohydroxyethers having the structural formula that corresponds to that of the novel amino compounds given above for compounds B with the proviso that only one of the R s in the formula is an alkyl group and R is the radical wherein R and y have the same values assigned above. In other words, the novel subgroup of aminohydroxyethers of the invention can be basically classified into three groups:

wherein R in each case is an alkyl group of up to 20 carbon atoms and R R and x have the values assigned above,

The same formula wherein only one of the R s is an alkyl group and the other is lower hydroxyalkyl, and R is the radical R1 -OCH;CH-CHCH 0-CH -(BR OH OH NH:

wherein R has the value assigned above; and

(III) The same formula as above wherein one R is alkyl, the other is hydroxyalkyl and R is the radical [OCH2OH] OH l. where R and y have the same values assigned above.

The preparation of the aminohydroxyethers of I is effected by oxyalkylating the corresponding dialkyl nitro alcohols with any of the oxyalkylating agents described above in molar ratios also described above, followed by reduction of the nitro group of the resulting nitrohydroxyether to the amino group. The aminohydroxyethers of II on the other hand can be prepared by oxyalkylating the monoalkyl amino alcohols with butadiene dioxide in a mole ratio of alcohol to butadiene dioxide of 2:1 and reducing the two nitro groups of the resulting nitro compound to amine groups. The aminohydroxyethers of III can be similarly prepared using an hydroxyalkyl, alkyl, nitroalkanol.

In carrying out the reduction step, I prefer to first neutralize any remaining catalyst with a base, such as calcium hydroxide, and then dissolve the nitro compound in methanol and hydrogenate it under hydrogenation conditions, for instance, at temperatures ranging from about 25 C. to C. and at a pressure of from about 400 to 500 p.s.i. in the presence of catalytic amounts of a nitro to amine reducing agent, e.g. a nickel catalyst such as Raney nickel catalyst. After the reduction has taken place, the amine can then be purified by any suitable means, such as distillation.

The new nitrogen, i.e. nitro and aminohydroxyether compounds of the invention, is useful as corrosion inhibitors, bactericides, pigment wetting and dispersing agents, emulsifiers and as intermediates in the preparation of nonionic surface active agents. For example, in utilizing either the nitro'or aminohydroxyethers as pigment wetting agents in a pigment system, I can add from about 2% to 8% by weight based on the weight of the pigment system of the compounds to a pigment'system containing a pigment, such as titaniumdioxide and water. The compounds thus act as wetting and dispersing agents for the pigment.

The following examples are ofifered to illustrate my invention; however I do notintend to be limited to the specific materials, preparations and' procedures shown. Rather, I intend for all equivalents obvious to those skilled in the art to be included within the scope of my invention.

Example I To a closed reactor equipped with an agitator containing 1071 grams of 2-nitro-2-methyl-1-propanol, having a temperature of 90 C., v'vere added lmillilitersof boron trifiuoride-diethyl ether. Ethylene oxide was thenjadded from a cylinder into the reactor at a pressure between 1 and psi/over a period of approximately 7 hours during which time the temperature of the reaction neveriexceeded 130 C. An oxyalkylated product containing 2- niethyl-2-nitro-4-oxa-6-hydroxyhexane was thereby produced. I

, grams of calcium hydroxide were then added to the reaction mixture and the mixture was thoroughly agitated. Three liters of methanol were then added to the mixture to form a slurry and the slurry was filtered. To the filtrate were then added 100 grams of Raney nickel and the thustreated filtrate was hydrogenated at a pressure of approximately 400 to 500 psi. at an initial temperature of 25 C. As the reduction proceeded, the temperature was gradually increased to approximately 50 C. The hydrogenation required a period of about 2 hours, during which time the reaction mixture was constantly agitated. After absorption of hydrogen had ceased, the reaction mixture was withdrawn from the container, the catalystremoved from the solution by filtration and the methanol separated from the reaction mixture by means of fractional distillation. The residue thus obtained was subjected to fractional distillation under vacuum. 2-methyl-6-hydroxy-4-oxa-2-hexylamine in-the amount of 100 grams was collected.

The following data was determined for the compound: Found: N, 10.51%; H, 11.18%;C, 53.45%. Calculated: N, 10.5%; H, 11.3%; C, 54.1%.

" i Example p One mole of 2-nitro-2-methyl-l-propanol is reacted with two moles of 1,2-epoxyethylbenzene in accordance with the general procedure of Example I to produce 2- methyl-2-nitro-4,7-dioxa-6,9-dipheny1-9-hydroxy nonane. This nitro compound is reduced as in Example I to obtain 2-methyl-9-hydroxy-4 ,7-dioxa-6,9-diphenyl-2-nonylamine.

Example III Example IV One mole of 2rnitro-2-methyl-l-propanol is reacted with two moles of 1,2-epoxyheptadecane in accordance with the general procedureof Example ,I to produce Z-methyl- 2-nitro-4,7-dioxa 6,9-dipentadecyl 9 hydroxy. nonane. This nitro compound is reduced as in Example I to obtain 2- rnethyl-9-hydroxy-4J dioxa 6,9 dipent'adecyl-2-nonylamine.

Example V One mole of 2-nitro-2-methyl-1 propanol is *reacted with one mole of chloropropylene oxide in accordance with the general procedure of Example I to produce 2- methyl-2-nitro-6-hydroxy-4-oxa 6 chloromethyl-6-hexyl alcohol. This nitro compound isreduced as in ExampleI to obtain 2-methyl-6-hydroxy-4-oxa 6 chloromethyl-Z- hexylarnine.

Example VI Example VII Two moles of 2-nitro-2-methyl-l-propanol is reacted with one mole of butadiene dioxide in accordance with the general procedure of Example I to produce 2,11-dimethyl-2,11-dinitro-4,9-dioxa 6,7 dihydroxy dodecane. This nitro compound is reduced as in Example I to obtain 2,11-dimethyl-6,7-dihyd'roxy-4,9-dioxa 2,11-dodecanediamine.

Example VIII One mole of 2-nitro-2-methyl-l-propanol is reacted with one mole of 1,2-epoxyethyl nitrobenzene in accordance with the general procedure of Example I to produce 2-methyl-2-nitro-4-oxa-6-nitrophenyl 6 hydroxy hexane. This nitro compound is reduced as in Example I to obtain 2-methyl-6 hydroxy-4-oxa-6-nitrophenyl-24hexylamine.

Example IX One mole of 2-nitro-2-methyl-l-propanol is reacted with two moles of propylene oxide in accordance with the general procedure of Example I to produce 2-met hyl- 2-nitro-4,7-dioxa-6,9-dimethyl-9-hydroxy nonane. This nitro compound is reduced as in Example I to obtain 2-methyl-9 hydroxy-4,7-dioxa-6,9-dimethyl-2-nonylamine.

Example X One mole of 3-methyl-3-nitro-2-butanol is reacted with one mole of ethylene oxide in accordance with the general procedure of Example I to produce 2,3-dimethyl-2- nitro-4-oxa 6 hydroxyhexane. 'Phis nitro compound is reduced as in Example I to obtain 2,3-dimethyl-6-hydnoxy-4-oxa-2-hexylamine.

Example XI One mole of 2-nitro-2-methyl-l-hexanol is reacted with one mole of ethylene oxide in accordance with the general procedure of Example I to produce 5-methyl-5- nitro-3-oxa-l-nonyl alcohol. This nitro compound is reduced as in Example I to obtain 5-amino-5-methyl-3- oxa-l-nonyl alcohol.

Example XII One mole of 2-nitro-2-methyl-l-nonadecanol is reacted with one mole of ethylene oxide in accordance with the general procedure of Example I to produce 18-methytl-18- nitro-20-oxa-22-hydroxy docosane. This nitro compound is reduced as in Example I to obtain 18-methyl-22-hydroxy-20-oxa-18-docosylamine.

Ex'ample XIII One mole of 12-nitro-12- methyl-l-tridecanol is reacted with one mole of ethylene oxide in accordance with the general procedure of Example I to produce 2-methyl-2- nitro14-oxa-16-hydroxy hexadecane. The nitro compound is then reduced as in Example I to obtain 2-metl'1yl-14- oxa-16-hydroxy-2-hexadecylamine.

Example XIV ,One mole of 6-nitro-6-ethy1-1-heptanol is reacted with one mole of ethylene oxide as in Example I to produce 2-et'hyl-2-nitro-8-oxa-10-hydroxy decane. This nitro compound is reduced as in Example I to obtain 2-ethyl-10- 'hydroxy-8-oxa-2-decylamine.

Example XV One mole of 2-nitro-2-methyl-l-propanol is reacted with 16 moles of ethylene oxide to produce 2-methyl-2- nitro 4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49-hexadeoa-oxa-S1-hydroxy-dopentacontane. This compound is reduced as in Example I to obtain 2 methyl-51-hydroxy- 4,7,10,l3,16,19,22,25,28,31,34,37,40,43,46,49 hexadecaoxa-2-dopentacontanylamine.

Example XVI One mole of tris(hydroxymethyl)nitromethane is reacted with three moles of ethylene oxide in accordance with the genenal procedure of Example I to produce tris (Z-hydroxyethoxy methyl)nitrometh ane. The compound is reduced as in Example I to obtain tris(2-hydroxyethoxy-methyl methylamine.

Example XVII One mole of tris(hydroxyethyl)tnitromethane and three moles of ethylene oxide are reacted following the procedure of Example I to give tris(Z-hydroxyethoxy-ethyl) nitromethane. The compound is reduced as in Example I to obtain tris(2-hydroxyethoxy-ethyl)methylamine.

Example XVIII Reaction of one mole of tris(hydroxyethyl)nitromethane with 2 moles of ethylene oxide following the procedure of Example I provides di(Z-hydroxyethoxy-ethyl) hydroxyethyl nitromet hane. Reduction of this compound as in Example I provides the corresponding amine.

Example XIX One mole of 2-nitro-2-methyl-l-propanol is reacted with one mole of butadiene monoxide in accordance with the procedure set forth in Example I to produce 2-nitro- 2 methyl 4 oxa-6-hydroxy-6-vinyl hexane. This ni'tro compound is reduced as in Example I to provide 2-methyl-4-oxa-6-hydroxy-6-vinyl-2-hexylamine.

Example XXI One mole of 2-nitro-2-methyl-l-propanol is reacted with one mole of styrene oxide using 1.2 percent of p-xylenesulfonic acid as catalyst instead of the boron trifluoride to produce 2-nitro-2-methy l-4-oxa-6-phenyl-6-hydroxy hexane which is reduced as in Example I to provide Z-methyl-4-oxa-6-phenyl-6-hydroxy hexylamine.

Example XXII One mole of 2-nitro-2-methyl-l-propanol is reacted with one mole of 3,4-epoxy-1-butano1 in accordance with the procedure of Example I to produce 2-nitro-2-methyl- 4-oxa-6- hydroxy-6-hydroxyethyl hexane which is reduced as in Example I to provide 2-methyl-4-oxa-6-hydroxy-6- hydroxyethyl-Z-hexylamine.

Example XXIII To a closed reactor equipped with an agitator containi'ngv a solution of 302 grams of tris(hydroxymethyl)nitromethane in 300 grams of isopropyl ether was added 1 milliliter of boron trifluoride-diethyl ether to form a reaction mixture. The reaction mixture was heated to about 37 C. Ethylene oxide was then added from a cylinder into the reactor at a pressure between 1 and 2 /2 p.s.i. over a period of approximately 11 hours during which time the temperature of the reaction never exceeded 75 C. At the completion of the 11 hour period the resulting material was heated under vacuum at about 50 C. to

remove the isopropyl ether. Tris(2 hydroxyethoxymethyl)nitromethane in the amount of 583 grams was obtained.

The following data were determined for the compound: Found: N (Dumas), 4.89%. Calculated: N, 4.8%.

Example XXIV The following is a stabilized steam cylinder oil whioh is adequately protected against bacteria by the addition of tris(2-hydroxyethoxy-methyl)nitromethane.

Percent by weight S.A.E. lubricating oil Oleic acid 10 Example XXV The following is a core oil which is adequately protected against bacteria by the addition of tris(2-hydroxyethoxymethyl)nitrornethane.

Percent by weight Crude tall oil 25 Fuel oil .35 Tall oil ester 40 Example XXVI The following is a cutting oil which is adequately protected by the addition of the nitrohydroxyethers of the present invention.

Percent by weight Tallow 65 Paraifin wax 29 Beeswax 29 Oxalic acid 1.3 Potassium citrate 1.3 Urea .4

Generically, the novel compounds of the present invention can be represented by the formula wherein R is a member selected from the group consisting of methyl and hydrogen; wherein R is a member selected from the group consisting of alkyl radicals of about 1 to 20 carbon atoms; lower hydroxyalkyl radicals; and a radical having the general formula: (CH -R R is a member selected from the group consisting of the radicals:

References Cited UNITED STATES PATENTS 8/1966 Frump 260615 XR 10/1949 Roach et al 260615 OTHER REFERENCES Lambert et al., Jour. Chem. Soc. (1947), pp. 1474- 1477.

LEON ZITVER, Primary Examiner.

H. MARS, Assistant Examiner.

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, D.C. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,402,208 September 17, 1968 I John A. Frump It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 38, in the formula, "R should read R Column 3, line 7, "dixoane" should read dioxane Column 8, line 31, "Beeswax 29" should read Beeswax 1.3

Signed and sealed this 27th day of January 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr. WILLIAM E. SCHUYLER, Attesting Officer Commissioner of Patents 

